The invention is generally directed to a portable compact device having a data interface for interfacing with an external information device, and in particular to the initialization of the contents of a data memory device in the portable compact device.
In general, there have been an absence of portable devices having data interfaces with external information devices until the present inventor introduced one disclosed in U.S. Pat. No. 4,534,012 entitled Portable Programmable Information Device and External Programming Station, which issued on August 6, 1985.
Reference is made to FIGS. 1 and 2 wherein simplified schematic drawings of the structure of the portable device constructed in accordance with the teachings of Pat. No. 4,534,012 are depicted. In FIG. 1, the data from the external device (not shown) passes through data input circuit 120 and is stored in memory circuit 121. Input data is then processed by center controlling circuit 122 as memo data, scheduled alarm data, alarm time data, machine language data (programming) and so forth, depending upon the type of information included in the input data. The data input from the external device is input in accordance with a predetermined data structure. By inputting data in accordance with this predetermined structure the portable device can be externally controlled. In addition, by inputting data through a keyboard 123 the input data can be modified. The input data may be displayed by a display circuit 124 or output to an alarm circuit 125.
However, the structure shown in FIG. 1 has a major problem. When no data is input from the external device, such as during the changing of batteries, the data is not processed by center controlling circuit 122, nor can it be modified by inputting data from a keyboard input 123. This is because a change in the data structure in memory circuit 121 does not enable center controlling circuit 122 to process the data stored in memory circuit 121.
Reference is now made to FIG. 2 wherein another schematic diagram of the portable device disclosed in U.S. Pat. 4,534,012 is depicted. In FIG. 2, the data from the external device (not shown) passes through input circuit 160 and is stored in memory circuit 161. The input data is then processed by center controlling circuit 162 in accordance with the data type indication contained in the input data. The data type indication is representative of the type of data, such as alarm data or memo data contained in input data. The input data types include, for example, memo data such as telephone numbers, addresses, and words, and scheduled alarm data which includes alarm time data and alarm comment data (which is displayed when the time coincides with the alarm-time data). In addition, the input data can include world time data which consists of place-name data and time difference data between a given place-name and a reference location. The input data may also include programming data for programming the operation of center controlling circuit 162.
Center controlling circuit 162 attempts to identify the type of data being input into the data input circuit 160 and, based on that information will properly process the data. In order to process the data at high speeds and with low electrical power usage, the structure of the input data is preset so as to include an indication of the type of data being transmitted. In addition, the data can be changed by way of a key input circuit 163.
However, the portable device described above has a major problem. If the data structure of the data stored in memory circuit 161 is different from the predetermined data structure, center controlling circuit 162 is unable to process the stored data. This type of problem can occur when the data input from the external information device is garbled or otherwise not accurately transmitted. In addition, changing the batteries can cause such a problem. When the structure of the data stored in memory circuit 161 is different from the proper data structure, the data stored in memory circuit 161 is not capable of being either processed by center controlling circuit 162 or corrected by key input circuit 163.
Accordingly, there is a need for a portable compact device in which a predetermined data structure is stored in the memory circuit and the data stored may be modified so it can be processed by the control circuit. There is also need to provide a predetermined data structure so that additional data may be entered in accordance with the predetermined data structure from a key input device without utilizing any external device. There is a further need for data to be entered from the key input even if the data structure stored in the memory circuit has been destroyed.